NBS can include the restoration of
natural flood plains, the protection and expansion of wetlands, the creation and restoration of oyster and coral reefs, and
investment into urban green spaces to reduce run-off. Such solutions are
designed and implemented through collaboration among local communities, civil
societies across sectors and different tiers of government. NBS then involve
multilevel governance across sectors and disciplines to protect, sustainably
manage and restore naturally occurring or modified ecosystems.

Such disasters have brought
conventional hard engineering solutions to the end of their tethers. NBS now
breathes new life into disaster risk management.

Rather than trying to control natural
hazards with more drains, seawalls and dams, governments are increasingly
turning to nature conservation for protection from
natural hazards.

NBS could now reduce local disaster
risks, nourish ecosystems and economies, and maximise human wellbeing and biodiversity. For
example, a designated urban wetlands area could be restored and conserved to
avert major flooding in flood-prone areas, and treat waste, complementing the
existing sewage management infrastructure.

Across disaster risk management and
water security sectors, NBS or “green infrastructure strategies” are engineered
to work in harmony with conventionally built infrastructure systems or “gray
infrastructure”. Green infrastructure strategies could now be part of broader
disaster and climate risk management strategies that complement gray
infrastructure measures like treatment facilities, sewer systems and stormwater
systems.

NBS approaches are reportedly
successful and cost-effective. The City of Portland in the US reduced urban flooding by 94 percent through
urban green infrastructure. In Vietnam, a mangrove restoration project
integrated with dike systems to reduce coastal flooding, saved some US$215
million. China’s “Sponge Cities” program,
which launched in 30 pilot cities, integrates vast swathes of green space into urban
design to reduce flooding.

Nature-based approaches are only just
being integrated into policy and investment. Developing nations and their
financiers including multilateral development banks and bilateral agencies, are
increasingly using NBS in water security, urban sustainability and other
development projects.

Some leading agencies involved in
conservation, environmental sciences and engineering, such as the World
Wildlife Fund (WWF), US Army Corps of Engineers, and International Union for
Conservation of Nature (IUCN) have taken initiatives to produce technical guidelines
on the planning, design and implementation of NBS.

The World Bank and the Global Facility
for Disaster Reduction and Recovery (GFDRR) generated a program that aims to
facilitate NBS, including in water management projects. Over the past seven
years, the World Bank’s disaster risk management (DRM) portfolio totalled some
US$50 billion. NBS components of DRM projects today total US$2 billion.